what is the lowest terms of 21/36
7/12 because you can divide 21 and 36 by 3 and you get 7/12 which you can't simplify anymore because 7 can't go into 12 and 12 can't go into 7.
first you take 21/36 and divided by the 3 because it is the greatest common denomenator and you get 7/12
